Nutritional quality and essential oil compositions of Thaumatococcus danielli (Benn.) tissue and seed

Evaluation of nutritional values, phenolic profile, aroma compounds and biological properties of Pittosporum tobira seeds

Background

Plant essential oils and phenolic compounds are widely used for their medicinal properties. Thus, the aim of this study is to evaluate the nutritional values, the chemical composition, antioxidant activity and anti-hemolytic effects of Pittosporum tobira seeds.

Methods

The aroma compounds were isolated using two methods (Headspace-solid phase microextraction (HS-SPME) and hydrodistillation (HD)) and analyzed by gas chromatography coupled with mass spectrometry (GC-MS). Bioactive phenolic compounds were identified by mean of high-performance liquid chromatography (HPLC-DAD). Reducing power, hydrogen peroxide (H₂O₂) scavenging and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assays were used to investigate antioxidant activity. Anti-hemolytic activity was evaluated using H₂O₂-induced hemolysis of red blood cells (RBC).

Results

Oxygenated sesquiterpenes, sesquiterpene hydrocarbons and oxygenated monoterpenes were the most volatile fractions identified by HD and HS-SPME coupled to GC-MS but their quality and amount were quite different according to the extraction methodology. The main phenolic compounds identified by HPLC were caffeic acid, followed by cinnamic acid and gallic acid. P. tobira seeds essential oils showed significant antioxidant activity in DPPH (IC₅₀ value = 1.5 mg/mL), H₂O₂ scavenging assay (IC₅₀ value = 159.43 μg/mL) and reducing power test (IC₅₀ value = 0.982 mg/mL) compared to methanolic extract. Moreover, the results revealed that the essential oil was able to protect RBC from hemolysis induced by H₂O₂. However, the methanolic extract had no effect on H₂O₂-induced hemolysis of RBC as compared to the essential oil and the standard vitamin C.

Conclusions

P. tobira may be used as a new natural source of antioxidant with therapeutic application in diseases caused by reactive oxygen species.

Graphical Abstract

Phytochemical Characterization and Biological Evaluation of Pittosporum tobira seeds

Chemical components of cold pressed kernel oils from different Torreya grandis cultivars

The chemical compositions of cold pressed kernel oils of seven Torreya grandis cultivars from China were analyzed in this study. The contents of the chemical components of T. grandis kernels and kernel oils varied to different extents with the cultivar. The T. grandis kernels contained relatively high oil and protein content (45.80-53.16% and 10.34-14.29%, respectively). The kernel oils were rich in unsaturated fatty acids including linoleic (39.39-47.77%), oleic (30.47-37.54%) and eicosatrienoic acid (6.78-8.37%). The kernel oils contained some abundant bioactive substances such as tocopherols (0.64-1.77mg/g) consisting of α-, β-, γ- and δ-isomers; sterols including β-sitosterol (0.90-1.29mg/g), campesterol (0.06-0.32mg/g) and stigmasterol (0.04-0.18mg/g) in addition to polyphenols (9.22-22.16μgGAE/g). The results revealed that the T. grandis kernel oils possessed the potentially important nutrition and health benefits and could be used as oils in the human diet or functional ingredients in the food industry.